駱靖宇,李學(xué)艷,李青松,姚寧波,陸保松,李國新,陳國元,廖文超,高乃云(.蘇州科技大學(xué)環(huán)境科學(xué)與工程學(xué)院,江蘇 蘇州 5009；.廈門理工學(xué)院水資源環(huán)境研究所,福建 廈門 604；.同濟(jì)大學(xué)污染控制與資源化研究國家重點(diǎn)實(shí)驗(yàn)室,上海 0009；4.浙江工業(yè)大學(xué)建筑工程學(xué)院,浙江 杭州 004)

紫外活化過硫酸鈉去除水體中的三氯卡班

駱靖宇1,2,李學(xué)艷1,李青松2*,姚寧波1,2,陸保松2,4,李國新2,陳國元2,廖文超2,高乃云3(1.蘇州科技大學(xué)環(huán)境科學(xué)與工程學(xué)院,江蘇 蘇州 215009；2.廈門理工學(xué)院水資源環(huán)境研究所,福建 廈門 361024；3.同濟(jì)大學(xué)污染控制與資源化研究國家重點(diǎn)實(shí)驗(yàn)室,上海 200092；4.浙江工業(yè)大學(xué)建筑工程學(xué)院,浙江 杭州 310014)

采用紫外活化過硫酸鈉(UV/PS)降解三氯卡班(TCC).考察了UV、PS和UV/PS聯(lián)用工藝去除TCC的效果,研究了PS投加量、反應(yīng)初始pH值和腐殖酸(HA)等因素對(duì)UV/PS降解TCC的影響,推測(cè)了UV/PS工藝中TCC可能的降解途徑,并對(duì)比了UV/PS和UV/H2O2工藝對(duì)TCC的去除效果和經(jīng)濟(jì)性.研究表明:UV與PS聯(lián)用能夠高效去除TCC,其降解過程符合擬一級(jí)動(dòng)力學(xué)模型(R2≥0.95);擬一級(jí)反應(yīng)速率常數(shù)k隨著PS投加量的增加先增大再減小,在PS投加量為250μmol/L時(shí),k達(dá)到最大值0.0810min-1;偏酸性條件(pH=6.0)有利于TCC的降解;HA對(duì)TCC的降解有抑制作用,抑制作用與HA的濃度呈正相關(guān); GC/MS鑒定表明, TCC降解過程中主要的中間產(chǎn)物有異氰酸4-氯苯酯和對(duì)氯苯胺,其可能的降解途徑為 TCC分子結(jié)構(gòu)中與酮羰基相連的 C-N鍵斷裂,脫氯,經(jīng)過一系列的反應(yīng)形成對(duì)氯苯胺和異氰酸 4-氯苯酯;UV/PS降解TCC過程中溶液中脫氯反應(yīng)導(dǎo)致Cl-濃度增加;與UV/H2O2工藝相比, 相同條件下UV/PS工藝中k值增大了96.65%,單位電能消耗量提高了97%.

UV/PS；三氯卡班；硫酸根自由基；中間產(chǎn)物

三氯卡班(triclocarban, TCC)是一種典型的藥品和個(gè)人護(hù)理用品(PPCPs),廣泛應(yīng)用于抗菌香皂、洗手液、化妝品和消毒劑中[1].其親水性低,親脂性強(qiáng)(pH=7.0時(shí),logKow為4.9)[2],物理化學(xué)性質(zhì)穩(wěn)定,自然環(huán)境中較難降解.研究表明 TCC對(duì)一些藻類和老鼠、魚類、蝸牛具有慢性毒性影響,還會(huì)導(dǎo)致人類癌癥、生殖功能障礙和發(fā)育異常等健康問題[3-8].近年來,不同水體中均檢測(cè)出了TCC[9-15].我國五大水系的TCC檢出率達(dá)到了的100%[16-17].目前,水體中的TCC已引起國內(nèi)外學(xué)者專家廣泛關(guān)注.

Gledhill[18]和Ying等[19]分別對(duì)TCC的生物降解做了相關(guān)的研究,發(fā)現(xiàn)生物去除TCC的效果不佳,且耗時(shí)長、條件嚴(yán)格;Sirés等[20]探究了電芬頓法對(duì)TCC的去除,去除效果受pH值影響大.傳統(tǒng)的水處理技術(shù)難以有效地去除水中的TCC[13,21-24],因此,亟待探尋水體中TCC經(jīng)濟(jì)有效去除的方法.UV活化PS具有反應(yīng)條件溫和、自由基產(chǎn)生快速、氧化性強(qiáng)且穩(wěn)定、無選擇性、操作簡單等特點(diǎn),逐步受到廣大學(xué)者的關(guān)注.

實(shí)驗(yàn)采用UV活化PS的工藝來去除水中的TCC,對(duì)比了UV、PS和UV/PS聯(lián)用三種工藝對(duì)TCC的去除效果,考察了 PS投加量、反應(yīng)初始pH值、腐殖酸(HA)和溫度等因素的影響,探討了TCC在UV/PS工藝中可能的降解途徑,以期為實(shí)際應(yīng)用中UV/PS降解水中TCC提供理論指導(dǎo)和實(shí)驗(yàn)基礎(chǔ).

1 實(shí)驗(yàn)部分

1.1 試劑與儀器

三氯卡班(TCC)(德國 Dr.Ehrenstorfer公司,純度＞99.5%);過硫酸鈉(PS)(AR,≥98.0%);腐殖酸(HA)(Tech,美國 Sigma-Aldrich);異氰酸 4-氯苯酯(德國 Dr.Ehrenstorfer公司,99.5%);對(duì)氯苯胺(德國Dr.Ehrenstorfer公司,≥98.0%),HCl、NaOH均為分析純;甲醇、乙腈(HPLC級(jí),德國 Merck); 30%過氧化氫(H2O2)(AR)實(shí)驗(yàn)室用水為 Mili-Q超純水(≤18.2M?).

LC-20A高效液相色譜儀(Shimadzu,日本),自動(dòng)進(jìn)樣器(SIL-20A),檢測(cè)器(SPD-M20A);氣相色譜質(zhì)譜聯(lián)用儀(GCMS-QP2010Ultra,日本島津);GC/MS自動(dòng)進(jìn)樣器(AOC-5000,日本島津),色譜柱(Rxi?-5ms: 30m×0.32mm×0.25μm,日本島津);離子色譜儀(戴安 ICS-1100);pH計(jì)(Eutevch,美國);HJ-6A型磁力恒溫?cái)嚢杵?江蘇金壇崢嶸儀器);HC-C18小柱(Anpel);紫外線光源(主波長254nm,楊紫特種紫外線光源,低壓汞燈,9W),紫外線強(qiáng)度計(jì)(TN-2365A,臺(tái)灣泰納).

1.2 實(shí)驗(yàn)方法

實(shí)驗(yàn)前開啟紫外燈預(yù)熱5min,然后置于燒杯中,保持紫外燈的位置相對(duì)燒杯固定,燒杯邊緣位置(圖中距離燒杯底部 8cm處的燒杯壁)的光強(qiáng)為11.5μW/cm2;投加一定量的PS溶液后打開紫外燈開始反應(yīng),分別在0、5、10、20、30、45、60min時(shí)取樣,隨即加入適量甲醇淬滅,經(jīng)0.45μm的玻璃纖維濾膜過濾后分析.GC/MS產(chǎn)物鑒定前用固相萃取對(duì)樣品進(jìn)行富集.反應(yīng)裝置見圖1.

圖1 實(shí)驗(yàn)裝置示意Fig.1 Schematic description of the reactor

1.3 分析方法

HPLC 條件:色譜柱為 Inertsil?ODS-SP(250mm×4.6mm,5μm);流動(dòng)相為乙腈:水=65:35 (V:V),流動(dòng)相流速為 1.0mL/min;檢測(cè)波長為265nm;進(jìn)樣體積為10μL; S/N＞3.

GC/MS條件:載氣為高純度氦氣,90kPa;進(jìn)樣量為1μL;無分流進(jìn)樣方式;進(jìn)樣口溫度為280℃;爐溫控制:初始溫度為60℃,保留時(shí)間安3min,然后以 5℃/min升溫至 150℃,持續(xù) 5min,然后以10℃/min升溫至280℃,持續(xù)3min;MS離子化溫度為 250℃;接口溫度為 280℃;采用 Scan掃描:質(zhì)荷比 m/z起始為 50,終止為 600,掃描時(shí)間為0～40min.

2 結(jié)果與分析

2.1 UV、PS和UV/PS工藝對(duì)TCC的降解

UV、PS和UV/PS工藝對(duì)TCC的降解結(jié)果如圖2所示.

圖2 PS、UV和UV/PS對(duì)TCC的降解效果Fig.2 Removal of TCC by direct UV irradiation, PS oxidation alone, and UV/PS process [TCC]=400μg/L, [PS]=0.25mmol/L, pH=6.0

實(shí)驗(yàn)表明,60min內(nèi)單獨(dú)PS對(duì)TCC的去除率小于 14%;單獨(dú) UV對(duì) TCC的去除增加至61.52%;相同條件下,UV/PS聯(lián)用對(duì)TCC的去除可達(dá)99.95%,表明UV/PS聯(lián)用工藝具有協(xié)同作用,可以更有效地降解TCC.TCC降解曲線的擬一級(jí)動(dòng)力學(xué)擬合結(jié)果表明,UV/PS工藝中擬一級(jí)動(dòng)力學(xué)常數(shù)k比單獨(dú)UV光降解的增大了4.6倍.

PS分子中含有過氧基且在水中可電離產(chǎn)生S2O82-,其氧化還原電位為2.01V,具有一定的氧化能力[25],因此,單獨(dú)PS對(duì)TCC有一定的降解能力;單獨(dú) UV照射下,對(duì) TCC降解起主要作用的是·O2[26].UV/PS工藝中,PS在UV的照射下,其中的O-O鍵會(huì)因吸收能量而斷裂,產(chǎn)生含有孤電子對(duì)的·SO4-,·SO4-不僅具有超強(qiáng)氧化性,還可以與水(H2O)或者氫氧根(OH-)反應(yīng)生成羥基自由基(·OH),增加溶液中自由基的濃度,使得TCC能夠高效降解,其反應(yīng)過程如方程(1)-(3)所示:

2.2 PS投加量的影響

實(shí)驗(yàn)中考察了PS投加量對(duì)UV/PS降解TCC的影響,不同PS投加量下TCC的降解曲線的擬一級(jí)動(dòng)力學(xué)擬合結(jié)果見圖3.

圖3 PS投加量對(duì)UV/PS降解TCC的影響Fig.3 Effect of PS concentration on TCC degradation by UV/PS process [TCC]=400μg/L, pH=6.0

由圖3可知,在實(shí)驗(yàn)范圍內(nèi),TCC的降解符合擬一級(jí)動(dòng)力學(xué)(R2≥0.91).PS投加量從 0增加到0.25mmol/L,擬一級(jí)動(dòng)力學(xué)常數(shù)k由0.0151min-1增大為0.0810min-1,PS投加量為0.25mmol/L時(shí),實(shí)驗(yàn)中60min TCC的降解率可達(dá)99.44%;繼續(xù)增加至0.75mmol/L,擬一級(jí)動(dòng)力學(xué)常數(shù)k反而減小為0.0344min-1.因此,UV/PS工藝中TCC的去除并不是隨著PS投加量的增加而越高.

由式(1)～(3)可知,PS濃度的增加可以提高溶液中自由基·SO4-和·OH的穩(wěn)態(tài)濃度,從而加速TCC的降解,因此,在投加量0～0.25mmol/L范圍內(nèi)TCC的去除隨著PS濃度的增加而增加;但有研究表明PS也會(huì)消耗·SO4-和·OH,生成氧化性較弱的·S2O8-[式(5)和(6)],影響 TCC的降解(PS與·SO4-和·OH 反應(yīng)的速率常數(shù)分別是 5.5× 105M-1s-1[27]和 1.4×107M-1s-1[28]),故實(shí)驗(yàn)中當(dāng) PS投加量較大(0.5mmol/L和 0.75mmol/L)時(shí) TCC的降解效果反而下降.

2.3 初始pH的影響

pH是影響高級(jí)氧化(AOPs)處理效果的重要參數(shù).實(shí)驗(yàn)中考察了pH對(duì)TCC去除的影響.不同pH值時(shí)TCC的去除擬合結(jié)果見圖4.

圖4 pH對(duì)UV/PS降解TCC的影響Fig.4 Effect of initial pH on TCC degradation by UV/PS process

實(shí)驗(yàn)中 pH值為 4.0、6.0、7.0、8.0和 9.5時(shí),60min內(nèi) TCC的去除率分別為 76.50%、99.44%、91.20%、91.71%和 74.74%.pH=6.0時(shí)TCC的去除率最高.

由圖 4可知,實(shí)驗(yàn)范圍內(nèi),隨著 pH的增大,k先增大后減小,在 pH=6.0時(shí),k達(dá)到最大值0.0810min-1.這與Saien等在考察pH對(duì)UV/PS去除水楊酸的影響時(shí)的研究結(jié)果相一致[29-31].

過硫酸根離子非催化反應(yīng)的活化能為33.5Kcal,而酸催化反應(yīng)的活化能為26.0Kcal[32],酸性條件下S2O82-會(huì)與H+發(fā)生酸催化反應(yīng)[33-34],因此過硫酸根在酸催化反應(yīng)中更易轉(zhuǎn)化為硫酸根自由基,產(chǎn)生更多的·SO4-[式(7)和(8)],促進(jìn)TCC的降解.但強(qiáng)酸條件下,更易發(fā)生式9和10的反應(yīng),反而消耗·SO4-產(chǎn)生氧化性更弱的自由基[35],導(dǎo)致TCC的降解速率降低.因此,相比于中性和強(qiáng)酸條件,偏酸性條件更有利于TCC的降解.

堿性條件下·SO4-會(huì)與 OH-反應(yīng)生成·OH(式3),但堿性環(huán)境中·OH的氧化性較弱[36],因此盡管堿性條件下有·OH產(chǎn)生,但效果沒有偏酸性和中性條件下好.有研究表明,堿性環(huán)境中大量生成的SO42-[式(3)]對(duì)·SO4-和·OH 均有抑制作用[31,37].因此,在一定 pH范圍內(nèi),偏酸性條件(本實(shí)驗(yàn)為pH=6.0)下TCC的降解效果更好.

2.4 腐殖酸的影響

腐殖酸(HA)是天然水體中主要的有機(jī)物,因此本實(shí)驗(yàn)采用 HA來模擬天然水體中的有機(jī)物(NOM),考察了HA對(duì)TCC去除的影響,結(jié)果如圖5所示.

實(shí)驗(yàn)中 HA 濃度為 0,0.5,1.0,3.0,5.0mg/L時(shí),TCC的去除率分別為 99.45%、96.99%、96.36%、89.03%和63.78%;另外由圖4可知,TCC降解的動(dòng)力學(xué)常數(shù) k隨著 HA濃度的增加由0.0810min-1減小到 0.0158min-1.表明 HA 對(duì)UV/PS降解TCC有著的抑制作用.

基于UV的高級(jí)氧化體系中HA有兩方面的影響,一方面,UV激發(fā)下NOM可以產(chǎn)生·OH、·O等活性自由基,促進(jìn)污染物的降解;另一方面NOM中的各種不飽和官能團(tuán)對(duì)UV有一定的吸收能力,削弱光的透射能力,同時(shí)會(huì)與目標(biāo)污染物競爭自由基[38].

實(shí)驗(yàn)中HA一直起抑制作用,原因可能是HA屏蔽了UV光輻射,降低了UV的活化作用;HA分子中的酚羥基、胺基、羧基等活性基團(tuán)與目標(biāo)污染物TCC競爭·SO4-和·OH等自由基,導(dǎo)致自由基的穩(wěn)態(tài)濃度降低[39].

圖5 腐植酸對(duì)UV/PS降解TCC的影響Fig.5 Effect of humic acid on TCC degradation by UV/PS process

2.5 UV/PS降解TCC的反應(yīng)途徑分析

TCC的初始濃度為 900μg/L, PS投加量0.25mmol/L,反應(yīng)60min后取出溶液固相萃取富集500倍后經(jīng)GC/MS鑒定,發(fā)現(xiàn)在9.97min和11.9min有兩個(gè)明顯的出峰(圖 6),特征離子碎片的質(zhì)荷比分別為 m/z=63,90,125,153和 m/z= 65,92,127.經(jīng)譜庫檢索鑒定為異氰酸 4-氯苯酯(1-chloro-4-isocyanato-benzen)和對(duì)氯苯胺(4-chloroaniline).

據(jù)此推斷出TCC的降解產(chǎn)物可能有異氰酸4-氯苯酯和對(duì)氯苯胺.TCC在UV/PS系統(tǒng)中可能的光降解途徑如圖7所示.

圖6 總離子色譜Fig.6 Total ion chromatogram (TIC)

圖7 TCC可能的光降解途徑Fig.7 Proposed reaction pathway for TCC degradation by UV/PS process

根據(jù)降解過程中中間產(chǎn)物的生成及Cl-濃度的增加,可以推測(cè)TCC的降解路徑:TCC分子結(jié)構(gòu)中酮羰基左側(cè)的C—N鍵(與二氯苯胺環(huán)相連)斷裂,形成異氰酸4-氯苯酯和3,4-二氯苯胺,然后3,4-二氯苯胺脫掉一個(gè)Cl形成對(duì)氯苯胺,這條降解途徑與丁世玲[26]的研究結(jié)果相似.還有一種可能的途徑:酮羰基兩側(cè)的 C-N鍵(分別與二氯苯胺環(huán)和對(duì)氯苯胺環(huán)相連)斷裂,經(jīng)過一系列的反應(yīng)形成主要中間產(chǎn)物對(duì)氯苯胺.TCC的降解過程中兩種降解途徑可能同時(shí)存在,異氰酸 4-氯苯酯和對(duì)氯苯胺等中間產(chǎn)物繼續(xù)被降解,生成其他物質(zhì),最終苯環(huán)開環(huán)轉(zhuǎn)化為CO2、H2O等[40-43].

2.6 TCC降解過程中主要成分的變化

實(shí)驗(yàn)考察了TCC的去除和降解產(chǎn)物的生成情況,結(jié)果見圖8.

TCC的快速降解發(fā)生在前30min,去除率達(dá)到 95.34%,之后反應(yīng)速率逐漸減小,在 60min時(shí)TCC濃度已經(jīng)低于檢出限.TCC降解產(chǎn)生異氰酸4-氯苯酯和對(duì)氯苯胺.在前15min異氰酸4-氯苯酯和對(duì)氯苯胺穩(wěn)定增加至 142.45μg/L 和169.55μg/L,然后開始緩慢減少,在 60min時(shí)濃度降低至70.30μg/L和100.55μg/L.從TCC的降解路徑分析,對(duì)氯苯胺的產(chǎn)生量應(yīng)該比異氰酸4-氯苯酯多,但其在反應(yīng)過程中的濃度一直比后者低,這可能是因?yàn)門CC分子結(jié)構(gòu)中的對(duì)氯苯胺環(huán)比二氯苯胺環(huán)降解更快[18]導(dǎo)致的.實(shí)驗(yàn)中隨著反應(yīng)的進(jìn)行,TCC分子結(jié)構(gòu)中的3個(gè)氯不斷脫離形成異氰酸 4-氯苯酯和對(duì)氯苯胺及大量 Cl-等,部分異氰酸4-氯苯酯和對(duì)氯苯胺降解也會(huì)有Cl-脫離,導(dǎo)致溶液中Cl-的濃度增大,在前15minCl-快速增加至242.73μg/L,之后Cl-的增加速率較之前有所下降,60min時(shí) Cl-濃度達(dá)到 429.19μg/L,這表明UV/PS可以快速降解TCC并脫氯,進(jìn)而可以降低溶液的毒性[44-45].

圖8 TCC降解過程中主要物質(zhì)的濃度變化Fig.8 Concentration changes of main products during TCC degradation by UV/PS process

在降解過程中TCC與異氰酸4-氯苯酯和對(duì)氯苯胺的摩爾比并不是 1:1.可能是因?yàn)樵诋惽杷?4-氯苯酯和對(duì)氯苯胺形成的同時(shí)一部分已經(jīng)被反應(yīng)消耗;可能有其它反應(yīng)途徑產(chǎn)生其它的中間產(chǎn)物,馮振濤等[46]的研究表明,有更為復(fù)雜的降解產(chǎn)物產(chǎn)生.

2.7 與UV/H2O2工藝比較

實(shí)驗(yàn)中對(duì)比考察了UV/PS與典型的高級(jí)氧化工藝UV/H2O2去除TCC的效能,結(jié)果見圖9.

圖9 UV/PS、UV/H2O2對(duì)TCC處理效果比較Fig.9 Removal of TCC by UV/PS and UV/H2O2processes

H2O2與 PS的投加量均為 250mmol/L時(shí), TCC的去除均遵循自由基反應(yīng)的擬一級(jí)動(dòng)力學(xué),反應(yīng)速率常數(shù)k分別是0.04117min-1(UV/ H2O2)和 0.08096min-1(UV/PS),相比 UV/H2O2, UV/PS降解TCC的k增加了96.65%.

表1 不同體系的單位電能消耗量和氧化劑成本Table 1 The electrical energy per order and oxidant costs in different systems

采用單位電能消耗量(EE/O)來評(píng)價(jià)兩種工藝的電能利用效率,其公式如下[47]:式中:EE/O:單位電能消耗量,kW·h/m3;P:紫外燈的功率,kW;V為時(shí)間t內(nèi)處理溶液的體積,L;k為反應(yīng)速率常數(shù),min-1.

EE/O值越低,體系中的電能利用率越高,效率也越高[48].

將反應(yīng)速率常數(shù) k帶入公式得到兩個(gè)體系的單位電能消耗表1所示,可以看出,UV/PS具有更高的電能利用率.另外,氧化劑的成本方面, UV/PS也略低于UV/H2O2.

3 結(jié)論

3.1 UV活化PS工藝能有效去除水體中的TCC,降解過程符合擬一級(jí)反應(yīng)動(dòng)力學(xué)模型,UV輻射強(qiáng)度為 11.5μW·cm-2,PS投加量為 250μmol·L-1, pH=6.0時(shí),60min的后,初始濃度為 400μg·L-1的TCC去除率可達(dá)99.44%.

3.2 TCC的去除隨PS投加量的增加和pH值的升高,先增強(qiáng)后減弱,偏酸性環(huán)境更有利于 TCC的降解,腐殖酸對(duì) TCC的去除有抑制作用,且抑制作用與腐殖酸濃度呈線性關(guān)系.

3.3 UV/PS降解TCC的中間產(chǎn)物主要有異氰酸4-氯苯酯和對(duì)氯苯胺,可能是TCC分子結(jié)構(gòu)中酮羰基兩側(cè)的C-N鍵斷裂產(chǎn)生的.

3.4 UV/PS聯(lián)用工藝比UV/H2O2工藝更加有優(yōu)勢(shì),其動(dòng)力學(xué)常數(shù)k提高了96.65%.

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Degradation of triclocarban aqueous solution through UV irradiation-activated sodium persulfate process.

LUO Jing-yu1,2, LI Xue-yan1, LI Qing-song2*, YAO Ning-bo1,2, LU Bao-song2,4, LI Guo-xin2, CHEN Guo-yuan2, LIAO Wen-chao2, GAO Nai-yun3(1.School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China；2.Water Resources and Environmental Institute, Xiamen University of Technology, Xiamen 361024, China；3.National Key Laboratory of Pollution Control and Reuse, Tongji University, Shanghai 200092, China；4.College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China). China Environmental Science, 2017,37(9)：3324～3331

Triclocarban (TCC) in aqueous solution was degraded by UV-activated persulfate. The removal efficiency of TCC by direct UV irradiation, PS oxidation alone, and UV/PS process was compared in this experiment. The effect of PS dosage, initial pH and HA on TCC degradation by UV/PS was investigated. The possible degradation approach and intermediates was proposed, meanwhile, the effect of degradation and economical efficiency for UV/PS were compared with UV/H2O2. The results showed that UV irradiation-activated sodium persulfate process could remove TCC efficiently and TCC degradation followed the pseudo-first order kinetic model well (R2≥0.95). The pseudo-first-order-constant k increased firstly and then decreased with the increase of PS dosage. The value of k reached a maximum of 0.0810min-1when the dosage of PS was 250μmol/L. Slightly acidic condition (pH=6.0) was better for TCC degradation. The removal of TCC was inhibited in the presence of HA, and the effect of inhibition was significantly positively correlated with the concentration of HA. 1-chloro-4-isocyanato-benzen and 4-chloroaniline were identified as the main intermediates by GC/MS. The possible degradation approach is that the C-N chemical bonds of the keto carbonyl group were broken during the degradation process, and thus 1-chloro-4-isocyanato-benzen and 4-chloroaniline was generated via the dechlorinationand other reactions. The concentration of Cl-was increased through the degradation process of TCC by UV/PS. Compared with UV/H2O2process, the pseudo-first-order-constant k and the electrical energy per order of UV/PS process increased by 96.65% and 97%, respectively.

UV/PS；triclocarban；sulfate radical；intermediates

X703

A

1000-6923(2017)09-3324-08

2017-02-28

國家自然科學(xué)基金項(xiàng)目(51378446,51678527,51408518);福建省科技計(jì)劃引導(dǎo)性項(xiàng)目(2017Y0079);福建省高校新世紀(jì)優(yōu)秀人才支持計(jì)劃項(xiàng)目(JA14227);福建省自然科學(xué)基金項(xiàng)目(2016J01695);江蘇省企業(yè)研究生工作站合作項(xiàng)目;廈門市科技局項(xiàng)目(3502Z20131157,3502Z20150051)

* 責(zé)任作者, 副研究員, leetsingsong@sina.com

駱靖宇(1992-),男,江蘇南通人,蘇州科技大學(xué)碩士研究生,主要研究方向?yàn)樗幚砝碚撆c技術(shù).